1. Field of the Invention
The present invention relates to an image pickup system and an image processing apparatus, and in particular to an image pickup system and an image processing apparatus for sequentially radiating illumination lights of a plurality of mutually different wavelength bands to perform image pickup of an object.
2. Description of the Related Art
In a medical field, operations using an apparatus which is minimally invasive to a living body, for example, like an endoscope have been conventionally performed.
As an observation method using an endoscope, for example, observation methods such as normal light observation in which an image with coloring almost similar to coloring in observation with naked eyes is obtained by radiating light of each of colors of R (red), G (green) and B (blue) to an object in a living body, and narrowband light observation in which an image in which blood vessels and the like existing on a mucosal surface layer of a living body are emphasized is obtained by radiating light of a band narrower than a band of illumination light for the normal light observation to an object in the living body have been conventionally known.
For example, Japanese Patent No. 4884574 discloses an endoscope system provided with a configuration capable of switching between observation modes corresponding to the normal light observation and narrowband light observation described above.
Further, the endoscope system disclosed in Japanese Patent No. 4884574 is configured as a system which performs such a frame-sequential operation that illumination lights of a plurality of mutually different wavelength bands are sequentially radiated to perform image pickup of an object, and a display image corresponding to one frame is generated with images corresponding to a plurality of fields obtained by performing image pickup of the object.
More specifically, Japanese Patent No. 4884574 discloses, for example, a configuration for, in the narrowband light observation, sequentially radiating narrowband green light nG1, narrowband blue light nB and narrowband blue light nB1 to perform image pickup of an object, performing addition processing of an image obtained in response to radiation of the narrowband blue light nB1 and an image obtained in response to radiation of the narrowband blue light nB to generate a narrowband blue-light image, and displaying a pseudo-color image generated by combining the narrowband blue-light image and an image obtained in response to radiation of the narrowband green light nG1 on a monitor.